Beneficial health effects associated with the consumption of dietary fruits and vegetables and free radicals especially have been associated with reducing the risk of various diseases including cardiovascular disease, cancer, atherosclerosis and other age-related diseases induced. Phenolic compounds are the most abundant hydrophilic antioxidants in the diet and the most active antioxidant compounds. Nijveldt R J, et al., Am J Clin Nutr 74:418-426 (2001). Hodgson J M, J Sci Food Agric 86:2492-2498 (2006). Erlejman A G, Free Radic Biol. Med 41:1247-1256 (2006). Moon Y J, Toxicol Vitro 20:187-210, (2006). Stangl V, Mol Nutr Food Res 50:218-228 (2006). Dudonn′e S, J Agric Food Chem 57:1768-4774 (2009). Jacobo-Vel′azquez D J Food Sci 74:R107-R113 (2009). The balance between antioxidation and oxidation is essential for maintaining health.
Stilbenes are a type of phenolic compound that include trans-piceatannol and trans-resveratrol (hereafter “piceatannol” and “resveratrol,” respectively). Stilbenes in general, and resveratrol in particular, have beneficial biological properties that include antibacterial and antifungal effects, as well as cardioprotective, anti-inflammatory, neuroprotective and anticancer actions. Resveratrol also has positive effects on longevity and age-related deterioration. Piceatannol and viniferins are other phenolic compounds that are usually found in lower concentrations than resveratrol in grapes and, as a result, their bioactivity has been studied less than that of resveratrol; nevertheless, some of their health-promoting properties including anticancer properties have been investigated. Raúl F. Guerrero et al; Innovative Food Science and Emerging Technologies 11 (2010) 231-238. Research has linked the antitumor activities of piceatannol to its ability to inhibit cell proliferation and arrest cells in the S phase. When compared to resveratrol, piceatannol is a stronger antioxidant and inducer of apoptosis.
Resveratrol is found in many different plants in significant quantities, including grapes, Japanese knotweed, peanuts, cocoa, strawberries, and Vaccinium berries; it is also found in red wine. Resveratrol became important in diets when examined in association with the so-called “French Paradox”. A diet high in fats but also high in red wine consumption results in a lower incidence of cardiovascular disease. The main component of red wine attributed to this benefit has been resveratrol.
Piceatannol is found in only a limited number of natural sources and at low levels. Piceatannol was first isolated as an antileukemic agent from the seeds of Euphorbia lagascae, and is also present in grape and Vaccinium berries. Other plants, such as Rheum spp., Machura pomifera, and Senna spp., have also been reported to contain piceatannol in very low concentrations. Due to the low levels of these stilbenes and their many health beneficial properties, new sources of the resveratrol and piceatannol are important. Of particular interest are methods of processing and methods of enhancing levels of these natural stilbene compounds in existing plants that would have beneficial uses in supplements, foods, and beverages.